Hello. I am kind of "newbie" on the forum here, have only been on a short time--I recently have started to get more serious about photography, taking my own pictures for a project I am working on. I have begun to realize how many wonderful old lenses are sitting around out there for next to nothing, and have collected a few. I am wondering about the "AF confirm" adapters I see listed online, especially on Ebay. So far I have only purchased the normal adapters (mainly Contax to EOS), and they work fine. Especially in dark or cluttered conditions, however, it is sometimes difficult to focus manually. Has anyone tried the "AF confirm" adapters? Do they really work? Are they as accurate as the autofocus on my digital and film bodies? Can they cause any problem for the camera?

If anyone has any opinion on them, I would very much appreciate hearing it.

AF confirm adapters usually work. The AF is a function of the body and not the lens, so the AF confirm adapters don't have to do much fancy to work; they just tell the camera body that a lens is attached and trying to focus. The focus sensors in the camera do the rest, with the same capabilities as for your autofocus lenses (so they may still have problems in dark conditions, depending on your camera body). I find focus confirm especially useful on slower, wider lenses (where it is nearly impossible to see the plane of focus in the viewfinder). The worst problem that I've heard of from malfunctioning focus confirm chips is making the camera lock up with an error while the lens is attached (but no lasting damage after the adapter is removed), and I've never had any such problems myself.

Thank you for your reply. Your explanation of how it functions brings to mind another question though--if I use a lens on an AF confirm adapter with my flash mounted on the camera, will the flash be able to help it focus as it does a normal AF lens? The flash--OK, I am going to sound extremely ignorant here--has whatever mechanism to help the camera auto focus in the dark, a beam or something. From the way you are explaining it, it sounds like it should have that capability as well with a lens on an AF confirm adapter.

I have an AF confirmation on Sony a700...it adapts my Nikkor (Nikon) lenses and other brands with the Nikon F mount to the Sony...I have also done the Nikon F mount conversion on a Sigma SD14 that actually feels and works better..the AF is on and off...I still find it better sometimes to not worry about the AF confirmation...and manually focus the lens....You just have to learn the soft spots and tweaks with each lens....The adapter I have has a glass element on it...however I can still take outstanding pictures with it...again you just have to play with it..so you know the lenses limits....most of the AF adapters do have the lenses inside...and do not let you focus to infinity....So if you can find one that does not have the lens...and do it manually you will come out ahead....I actually take better pictures with my SD14 with a lower resolution and no AF confirmation than with the Sony a700...that has the AF confirmation...I have not had the Sony as long as the SD14....so I bet over time my shots will get better....I will put a couple up for you to judge...About the flash...I usually use it on manual mode were you dial in the distance and lens you are using...works better that way...

Sony a700 with Zeiss 1.4/50 ZF using AF confirmation adapter



Sigma SD14 converted to Nikon F Mount with Nikkor 200mm F2 ED



Hope this helps you out a little bit..

Tony C.

tc95 wrote:
I have an AF confirmation on Sony a700...it adapts my Nikkor (Nikon) lenses and other brands with the Nikon F mount to the Sony...

Does this adaptor give Infinity Focus? If so, where can I get one? I'm very fond of the A700, but I own too many Nikon lenses to make getting one practical without an infinity-focus capable adaptor.

Chococat,

Lookee here:

http://www.fredmiranda.com/forum/topic/713817


This looks to be the new uber-chip.

I haven't yet got the EXIF data to program (the seller has been very helpful with emails, but his English is shakey.) But the focus confirmation, and auto-shutter feature are working GREAT.

BTW, the term "AF confirm" is a misnomer. They are really "focus confirm" chips.

mawz wrote:
Does this adaptor give Infinity Focus? If so, where can I get one? I'm very fond of the A700, but I own too many Nikon lenses to make getting one practical without an infinity-focus capable adaptor.

You can do a search here re infinity focus. It's actually a bit complicated, as far as what the GOAL is. However, as far as achieving whatever focus-goal you decide on, the basics are:

1: The adapter must be of the proper thickness. Some cheaper ones are not.

2: Many lenses (Zeiss, Zuiko... not sure about Nikon) have adjustment screws hidden under the rubber rings. You get close with a good adapter, then fine-tune to taste. Plenty of info here is you do a search.

I'm not certain about the flash question (I'm travelling and don't have my flash with me to test it out), but I would guess that the flash assist beam (usually a deep red, nearly IR light that is dim to human eyes but very bright to the AF sensor) would still emit (someone who can test this out, please correct me if I am wrong), just as it would with any other lens attached. A lot of the focus confirm chips trick the camera into thinking a 50f2 lens is attached (regardless of the actual manual focus lens's focal length/aperture), so if you have a zoom flash that adjusts for lens focal length, you will probably have to manually set the flash zoom for the appropriate coverage.

Cableaddict wrote:
mawz wrote:
Does this adaptor give Infinity Focus? If so, where can I get one? I'm very fond of the A700, but I own too many Nikon lenses to make getting one practical without an infinity-focus capable adaptor.

You can do a search here re infinity focus. It's actually a bit complicated, as far as what the GOAL is. However, as far as achieving whatever focus-goal you decide on, the basics are:

1: The adapter must be of the proper thickness. Some cheaper ones are not.

2: Many lenses (Zeiss, Zuiko... not sure about Nikon) have adjustment screws hidden under the rubber rings. You get close with a good adapter, then fine-tune to taste. Plenty of info here is you do a search.

I'm aware of the issues that determine infinity focus with the EOS adaptors, And BTW, Nikon-EOS adaptors achieve Infinity Focus reliably.

I'm unaware of any Nikon->Sony Adaptors which can achieve infinity focus, and that's what I'm asking the tc95 about, as he's adapting Nikon to Sony/Minolta A mount which is more difficult than adapting to EOS as A mount has a smaller interior diameter and a longer register (although the register isn't a huge issue with F mount as you're going from a 2.5mm difference to a 2mm difference, more than enough to fit an adaptor, it's the mount diameter issue that's the kicker)

Mawz,

The adaptor does not do infinity focus due to the lens inside of it...you can get really close..however, when you start working with the picture is is soft like my first picture above....it is sharp you still have some of the soft edges....I would say 50% of my shots are not at infinity focus.....so really does not matter to me...If you look for one without the lens...it like using an extension tube...so you start getting into the macro arena.....if you like the A700...I would see if you can pick one up cheaply...and the Minolta AF lenses are a steal right now...I picked up two from a local camera store for $50.00 each...because they do not know what to do with them....it is actually a fun camera....still have the learning curve with mine right now...now the Sigma SD14 that I have converted to Nikon F mount give me infinity focus...and the Foven Sensor produces some very nice color and the whole thing can be picked up for less than $600.00 with the conversion adapter...

Sony to Nikon F Mount Adapter Ebay

This is a picture I just took with the adapter on a Sony A700 using Nikkor-H 50mm F1.2 Manual focus lens...f-stop at 11 ISO 100 with built in flash....contrast and minimal manipulation, cropped at 65% to 75%...at infinity focus




Install guid Nikon F mount on Sigma SD14
They also make Sigma to Leica

Tried to set up the same shot...using sigma SD14 converted to Nikon Mount with a Nikkor-H F1.2 Manual focus lens f-stop 2 ISO 100 with built in flash....minimal manipulation, cropped to 70%...at infinity focus


Ebay Auction for Sigma Adapter

Hope this helps out a little..

Tony C.

tc95 wrote:
Mawz,

The adaptor does not do infinity focus due to the lens inside of it...you can get really close..however, when you start working with the picture is is soft like my first picture above....it is sharp you still have some of the soft edges....I would say 50% of my shots are not at infinity focus.....so really does not matter to me...If you look for one without the lens...it like using an extension tube...so you start getting into the macro arena.....if you like the A700...I would see if you can pick one up cheaply...and the Minolta AF lenses are a steal right now...I picked up two from a local camera store for $50.00 each...because they do not know what to do with them....it is actually a fun camera....still have the learning curve with mine right now...now the Sigma SD14 that I have converted to Nikon F mount give me infinity focus...and the Foven Sensor produces some very nice color and the whole thing can be picked up for less than $600.00 with the conversion adapter...


Hope this helps out a little..

Tony C.

Thanks for the info, the adaptor won't do what I need (I'm not able to use optical-based adaptors, just bare mount adaptors that provide infinity focus. I need both infinity and the full lens speed while optical adaptors cost lens speed and quality)

An example of where I need ful lens speed and infinity:

Mawz,

You might want to look into the Sigma SD14...with converted mount...I actually love mine....and really a bargain...about $400 US for the camera and adapter $150 US...you can do it yourself...and a fun camera with great colors...

Tony C.

PS Nice shot

Not infinity but the same SD14 converted camera with Nikon 200mm F2 manual focus....I am crazy some time...

tc95 wrote:
Mawz,

You might want to look into the Sigma SD14...with converted mount...I actually love mine....and really a bargain...about $400 US for the camera and adapter $150 US...you can do it yourself...and a fun camera with great colors...

Tony C.

PS Nice shot

Not infinity but the same SD14 converted camera with Nikon 200mm F2 manual focus....I am crazy some time...



Nice shot, nice lens.

The SD14 would be a downgrade from my D40 for my uses, let alone my D300. I've not been impressed by Sigma's kit, particularly for high ISO work which I do a fair bit of. The odd and smallish crop factor is an issue as well.

I'd been looking at the A700 because it's got great ergonomics and performance (unlike the SD14) and its high ISO performance is quite good with the v4 firmware and it offers in-body IS which my D300 does not, and in-body IS is quite useful for my sort of low-light work.